Certain metals, such as cobalt, copper, iron, manganese, and zinc, play an essential role for optimal health. Cobalt is the key constituent of vitamin B12, which is a cofactor for methylmalony-CoA mutase and methionine synthase in humans. (Sigel et al., Met. Ions Life Sci. 13 (2013) 295-320). Copper is essential in any organism that have an oxidative metabolism. (Scheiber et al., Met. Ions Life Sci. 13 (2013) 359-387). Copper is a component of multiple enzymes involved in reducing molecular oxygen; of multiple enzymes involved in metabolizing substances such as histamine, serotonin, epinephrine, and dopamine; of multiple enzymes that oxidize ferrous iron and facilitate binding of iron to transferrin; and of cytochrome c oxidase, which is a critical player in energy production. (Council for Responsible Nutrition. Recommended Intakes of Vitamins and Essential Minerals; 2002). While iron is also a component of multiple enzymes, for example cytochromes, iron-sulfur enzymes, and other enzymes, iron is also an important part of hemoglobin and myoglobin, which play the important role of oxygen diffusion facilitators in tissues. (Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington (DC): National Academies Press (US); 2001. 9, Iron). As with the other metals, manganese and zinc are components of various enzymes. Manganese is involved in enzymes playing roles in the formation of bone and in the metabolism of amino acids, lipids, and carbohydrates. (Council for Responsible Nutrition. Recommended Intakes of Vitamins and Essential Minerals; 2002). Zinc functions as a component of numerous enzymes in the maintenance of the structural integrity of proteins and in the regulation of gene expression. (Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington (DC): National Academies Press (US); 2001. 12, Zinc).
Other minerals, such as nickel, have not been given essential mineral status, but their role in structure components or cofactors for enzymes suggest they also play important roles for optimal health. Nickel is a cofactor or structural component of metalloenzymes involved in hydrolysis, redox reactions, and gene expression, among other functions. (Institute of Medicine (US) Panel on Micronutrients. Dietary Reference Intakes for Vitamin A, Vitamin K, Arsenic, Boron, Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon, Vanadium, and Zinc. Washington (DC): National Academies Press (US); 2001. 13, Arsenic, Boron, Nickel, Silicon, and Vanadium).
While the best way to get minerals into the body needs is by eating a variety of foods, sometimes a mineral supplement is needed. Since the use of chelated minerals, where a metal ion is bound to a chelating agent, to supplement minerals in animal feed, mineral supplements for human consumption also started using chelated metals as dietary supplements. However, the cost of chelating minerals has provided the widespread use of chelated minerals in spite of experimental data showing that chelated metals have bioavailability. Thus there is a need for lower cost methods for synthesizing chelated minerals.